They are guessing like most airline managements these days. And making plans to be able to handle a potential uptick in traffic based on those guesses.
They have about 1700 pilots categorized as "unassigned", i.e., no airplane, seat or base but still on the payroll (not laid off). They recently announced their intention to have all 1700 back by October of this year.
They also have ~1350 mandatory retirements through 2023.